winrt: mouse handling: Fix detection of affected window

With the previous implementation the detection of the
affected window (windowAt which uses QWindow::geometry)
only worked for the upper left quarter of the window,
when used on a High DPI screen. As QWindow does not use
native positions, the mouse cursor's position has to be
mapped before checking the window under the mouse.

Change-Id: I1a30b9669ec3e4c573cf83aed57c20d65675ff16
Reviewed-by: Andre de la Rocha <andre.rocha@qt.io>
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@qt.io>

1 files changed, 3 insertions, 2 deletions

diff --git a/src/plugins/platforms/winrt/qwinrtscreen.cpp b/src/plugins/platforms/winrt/qwinrtscreen.cpp
index 7b9502f9ab..1a5af22814 100644
--- a/src/plugins/platforms/winrt/qwinrtscreen.cpp
+++ b/src/plugins/platforms/winrt/qwinrtscreen.cpp
@@ -47,6 +47,7 @@
 #endif
 #include "qwinrtwindow.h"
 #include <private/qeventdispatcher_winrt_p.h>
+#include <private/qhighdpiscaling_p.h>
 
 #include <QtCore/QLoggingCategory>
 #include <QtGui/QSurfaceFormat>
@@ -1126,11 +1127,11 @@ HRESULT QWinRTScreen::onPointerUpdated(ICoreWindow *, IPointerEventArgs *args)
     // Common traits - point, modifiers, properties
     Point point;
     pointerPoint->get_Position(&point);
-    QPointF pos(point.X * d->scaleFactor, point.Y * d->scaleFactor);
+    const QPointF pos(point.X * d->scaleFactor, point.Y * d->scaleFactor);
     QPointF localPos = pos;
 
     const QPoint posPoint = pos.toPoint();
-    QWindow *windowUnderPointer = windowAt(posPoint);
+    QWindow *windowUnderPointer = windowAt(QHighDpiScaling::mapPositionFromNative(posPoint, this));
     QWindow *targetWindow = windowUnderPointer;
 
     if (d->mouseGrabWindow)